brown rot pandemic

[Rick]

We have lovely white clay rich in lime so the bricks tend to be very alkaline. I must admit that maybe this is still a problem and a top dress with CaSO4 is still a good idea. It surely can't do any harm now.

Thanks

See if you can get a hardness check on leachate water.

Alkalinity is from hydroxides and carbonates (not calcium or maganesium). Alkalinity (HCO3 or OH) can be associated with any major cation (Na/K/Ca/Mg), and even if you demonstrated a high pH coming off the clay, it doesn't neccessarly mean you have high alkalinity.

Hardness measures Ca/Mg (with aluminum interference). You may have a high Ca clay, but once fired it may have no mobile Ca. So to determine mobile (bioavailable) Ca you need to measure hardness and not pH or alkalinity.

 

[Rick]

I personally dont think that Ca/Mg or aspirin will fix the problem if it already in the plant(s).

you can use a preventer like physan 20

I generally agree that Ca/Mg/asprin will not "cure" a present infection.

However I've seen more people end up with all new problems after playing with Physan.

At one point I was able to find the company field research on Physan specifically for Erwinia infections.

The efficacy rate (or rate of cure) was less than 10% compared to doing nothing at all. Except for being statistically significant, it really doesn't seem very effective.

Antibiotics (like carbenocilyn) are perported to do better.

I've had good results with cinamon, surgery, and Dragons Blood.

But since the change in nutrition, I've had little need of "curing" bacterial rots, and I don't use pharmacutical or industrial chemicals as preventatives.

 

[keithrs]

I generally agree that Ca/Mg/asprin will not "cure" a present infection.

However I've seen more people end up with all new problems after playing with Physan.

At one point I was able to find the company field research on Physan specifically for Erwinia infections.

The efficacy rate (or rate of cure) was less than 10% compared to doing nothing at all. Except for being statistically significant, it really doesn't seem very effective.

Antibiotics (like carbenocilyn) are perported to do better.

I've had good results with cinamon, surgery, and Dragons Blood.

But since the change in nutrition, I've had little need of "curing" bacterial rots, and I don't use pharmacutical or industrial chemicals as preventatives.

I was not talking about using Physan as a "cure" to infected plant only as a preventative to kill pathogens that may be in the grow area and in the pots.

I as well have had zero need for chemicals since using Sub Culture B.

I have never used cinnamon or dragon blood.... Sh*t, I have no clue what that even is! Just a good old hot knife.

If it worth anything....Seaweed is said to stimulate the plants SAR as well.

 

[keithrs]

keithrs, why use a fungicide if it is bacterial rot?

Phyton 27 is a systemic Fungicide/bactericide that will protect the plant from bacterial soft rots. I use it after I remove the infected tissue.

 

[Erythrone]

Sorry keithrs. I was not thinking about Phyton 27. I asked you that because your wrote: "I think you'll need to use a systemic fungicide several times if your going to have any chance. Spray everything around your grow area."

But now I understand that you were writing about a fungicide/bactericide

 

[Rick]

I as well have had zero need for chemicals since using Sub Culture B.

Label ingredients on Sub Culture B is some beneficial bacteria and a low dose of a low K fert.

Sub Culture M is a mycorrhizae / beneficial bacteria inoculate with kelp.

So if you add Sub B to regular surface water you get a low K high Ca/Mg fert with beneficial bacteria. Can't hurt!

I've added things like SubC M before and got mixed results. Definitely didn't prevent erwinia.

http://www.slippertalk.com/forum/showthread.php?t=7208

I messed with a mycorrhizae inoculate back in 2008

 

[keithrs]

The trichoderma is the important one. Rootshield is an all trichoderma product. I have recently started to use a product from a guy off eBay.

 

[Rick]

The trichoderma is the important one. Rootshield is an all trichoderma product. I have recently started to use a product from a guy off eBay.

The Plant Success product I used had two species of trichoderma in it.

 

[Cochlopetalum]

I use a powder of trichoderma to dust roots, when I repott new plants. I find it to be effectiv on fungus like Fusarium, Pythium and Phytophthora, I think it have saved me some Phalls and paphs with realy bad rot.

 

[Rick]

A concept to consider about the presence/absence of beneficial microbes is to ask why they are generally present in natural soils and not in orchid potting mixes already (especially when we see disease in our plants).

In practice you should be able to inoculate a potting mix once, and if the environment is conducive to these microbes they should proliferate and keep everyone happy forever. These same microbes have been noted on orchid roots in the wild, so what happens to them in transfer and pot culture that makes them go away?

The logic is similar to what I've proposed generally with low k feeding and using moss as indicators of good pot conditions.

 

[keithrs]

A concept to consider about the presence/absence of beneficial microbes is to ask why they are generally present in natural soils and not in orchid potting mixes already (especially when we see disease in our plants).

In practice you should be able to inoculate a potting mix once, and if the environment is conducive to these microbes they should proliferate and keep everyone happy forever. These same microbes have been noted on orchid roots in the wild, so what happens to them in transfer and pot culture that makes them go away?

The logic is similar to what I've proposed generally with low k feeding and using moss as indicators of good pot conditions.

I agree....

One thing that comes to mine is that salts effect the life of microbes.

I will be trying N fixing microbes next spring.

 

[Erythrone]

N fixing microbes for orchids??

 

[Rick]

I agree....

One thing that comes to mine is that salts effect the life of microbes.

I will be trying N fixing microbes next spring.

Yes

I also noticed that the microbes in Sub Culture B where listed as "high salt" adapted species. Although the trichoderma were not part of Sub Culture B.

One thing I found in the moss literature was that moss assemblages often include blue-green algae that are N fixing species. So since orchids are frequently associated with mosses, it's not unlikely that the orchids are getting their fixed N from the blue-green algae in the moss.

 

[keithrs]

Yes

I also noticed that the microbes in Sub Culture B where listed as "high salt" adapted species. Although the trichoderma were not part of Sub Culture B.

Not sure your source.. But the back of the package I have here list two spp of trichoderma.

 

[Rick]

Not sure your source.. But the back of the package I have here list two spp of trichoderma.

The label was upside down on the web, so I might have missed them by the time I flipped and scrunched the label.

I saw the trichoderma on the Sub Culture M though.

reviewing the labels I see T. harzianum for SC B, but SC M has both T harzianum and T. konigii.

 

[keithrs]

The label was upside down on the web, so I might have missed them by the time I flipped and scrunched the label.

I saw the trichoderma on the Sub Culture M though.

reviewing the labels I see T. harzianum for SC B, but SC M has both T harzianum and T. konigii.

Your right only one is listed...

 

[TyroneGenade]

This funny infection my plants have is getting more and more interesting. Last year one of my Eulophia speciosa growths rotted (or so I thought). This years, same things: the new leaves began to rot and die back. Fearing the worst I took the think out of its pot and lo-and-behold, the tuberoids were A-OK. Even last year's growth that rotted still had a healthy tuber. There was no damage to the plant itself, it is only the new leaves. On closer examination I see my L. anceps (both of them) all have new growths which are dying back. What ever this it isn't killing the plant, only the new leaves (which is death to a Paph or Phrag). Maybe something has changed in my water supply? I begin to doubt this is a real infection but maybe a mineral shortage or something.

 

[Rick]

This funny infection my plants have is getting more and more interesting. Last year one of my Eulophia speciosa growths rotted (or so I thought). This years, same things: the new leaves began to rot and die back. Fearing the worst I took the think out of its pot and lo-and-behold, the tuberoids were A-OK. Even last year's growth that rotted still had a healthy tuber. There was no damage to the plant itself, it is only the new leaves. On closer examination I see my L. anceps (both of them) all have new growths which are dying back. What ever this it isn't killing the plant, only the new leaves (which is death to a Paph or Phrag). Maybe something has changed in my water supply? I begin to doubt this is a real infection but maybe a mineral shortage or something.

Do you have a TDS or conductivity meter? I found this a pretty critical piece of equipment recently.

 

[dodidoki]

This funny infection my plants have is getting more and more interesting. Last year one of my Eulophia speciosa growths rotted (or so I thought). This years, same things: the new leaves began to rot and die back. Fearing the worst I took the think out of its pot and lo-and-behold, the tuberoids were A-OK. Even last year's growth that rotted still had a healthy tuber. There was no damage to the plant itself, it is only the new leaves. On closer examination I see my L. anceps (both of them) all have new growths which are dying back. What ever this it isn't killing the plant, only the new leaves (which is death to a Paph or Phrag). Maybe something has changed in my water supply? I begin to doubt this is a real infection but maybe a mineral shortage or something.

Hello!
I hope I can help you. My problem was similar for more than 2 years, I thought that I give up dealing with orchids because this problem. I tried everything, drier conditions, cinnamon, Cu, every fungicides, all of were insufficient. This diseases killed many of my catts, eg. dowiana rosita ( I was very sad...), symptoms were similar: all of new growths turned to black and died. All of new, otherwise healthy plants were put in my greenhouse showed the sign of diseases within few days: started new growts rotted black within a week.
After reading many of articles I accused Pseudomonas , it is a bacteria wich is resistent against fungicides, of course, spreads with water ( even by humidifier, tha explains rapid spreading)quickly.
After than I spayed my plants with ciprofloxacine and using 1,5 ml/l NaOCl 5% solution for desinfecting water. Symptoms disappeared within a week and can't be seen in my culture for more than a year.

 

[Erythrone]

The label was upside down on the web, so I might have missed them by the time I flipped and scrunched the label.

I saw the trichoderma on the Sub Culture M though.

reviewing the labels I see T. harzianum for SC B, but SC M has both T harzianum and T. konigii.

So it should better to use SC M???